Based on clinical trials since 1963, it appears that breast examination (CBE) in combination with mammography may be the best strategy for high sensitivity and specificity in breast cancer screening provided CBE can be quantitative with digital (and standardized) reporting. Quantitative imaging of the palpable structure of the tumor may help decipher the abnormal changes in the breast and sentinel lymph nodes over time. An inexpensive, noninvasive screening tool with the ability to detect tumors as small as ~5mm could be used in a sequential approach to early detection. The long- term objective of this research is to develop a thin-film nanodevice, i.e., electronic skin, that will convert the pressure distribution on physical contact to light that can be imaged directly on a digital camera at a resolution on par with the human finger (~20 <m). By scanning with the handheld tool, similar to CBE, a quantitative image of the nodular structure of the breast and sentinel lymph node scoring of the local hardness will be obtained. The image will be digitally stored containing quantitative information on both size and hardness of palpable nodules. There are three specific aims for this project: 1) to make a nanodevice to quantitatively study its performance to measure size of the high modulus palpable mass (resolution), determine the lowest modulus of palpable mass that is detectable (contrast), determine the average applied stress needed to produce a quantitative image of the mass (sensitivity), and hardness of the mass (scoring);2) study and quantify the effect of the depth of the palpable mass beneath the surface on imaging (depth resolution), study the effect of average applied stress on depth resolution, and study the nature of the palpable mass;and 3) perform a similar analysis as described in Specific Aims 1 and 2 on an artificial breast with a nodular structure in order to quantitatively understand the effect of curvature on the measured image. PUBLIC HEALTH RELEVANCE Development of an inexpensive, noninvasive, handheld screening tool for early detection of breast cancer that can image the palpability of a tumor and the nature of its attachment to surrounding tissue will enable family physicians and other clinicians to screen patients who do not have access to the more expensive screening tool and avoid unnecessary exposure to radiation used in mammography. The quantitative image with size, hardness, and palpability of the mass will provide a set of orthogonal measurements that will significantly improve the procedure of clinical breast examination (CBE) and improve specificity, i.e., low false positives, to help physicians make well-informed decisions to perform further testing and initiate therapy at the earliest stages of breast cancer.